signal.c

嵌入式VxWorks开发所需典型例程源代码

/* includes */
#include "vxWorks.h"
#include "sigLib.h"
#include "taskLib.h"
#include "stdio.h"
#include "logLib.h"

/* function prototypes */
void catchSIGINT(int);
void sigCatcher(void);
 
/* globals */
#define NO_OPTIONS 0
#define ITER1 100
#define LONG_TIME 10000
#define HIGHPRIORITY 100
#define LOWPRIORITY 101
int ownId;

void sigGenerator(void) /* task to generate the SIGINT signal */
{
	int i, taskId;
	STATUS taskAlive;
	logMsg("$$$$$$$$$----BEGING----\n",0,0,0,0,0,0);

	if((taskId = taskSpawn("signal",100,0x100,20000,(FUNCPTR)sigCatcher,0,0,0,0,0,0,0,
				0,0,0)) == ERROR)
		printf("taskSpawn sigCatcher failed\n");

	ownId = taskIdSelf(); /* get sigGenerator's task id */

	taskDelay(10); /* allow time to get sigCatcher to run */

	for (i=0; i < ITER1; i++)
	{
		if ((taskAlive = taskIdVerify(taskId)) == OK)
    		{
    			logMsg("++++++++++++SIGINT sinal generated\n",0,0,0,0,0,0);
    			kill(taskId, SIGINT); /* generate signal */
    			/* lower sigGenerator priority to allow sigCatcher to run */
    			taskPrioritySet(ownId,LOWPRIORITY);  
    		}
    		else  /* sigCatcher is dead */
    			break; 
	}  
	printf("\n***************sigGenerator Exited***************\n");
}

void sigCatcher(void) /* task to handle the SIGINT signal */
{
	struct sigaction newAction;
	int i, j;

	newAction.sa_handler = catchSIGINT; /* set the new handler */
	sigemptyset(&newAction.sa_mask); /* no other signals blocked */
	newAction.sa_flags = NO_OPTIONS;	/* no special options */

	if(sigaction(SIGINT, &newAction, NULL) == -1)
		printf("Could not install signal handler\n");

	for (i=0; i < ITER1; i++)
  	{
      		logMsg("Normal processing in sigCatcher\n",0,0,0,0,0,0);
		/*for (j=0; j < LONG_TIME; j++);*/
		taskDelay(1);
    	}
  	
	printf("\n++++++sigCatcher Exited+++++++++\n");
}


void catchSIGINT(int signal)  /* signal handler code */
{
	logMsg("----------SIGINT signal caught\n",0,0,0,0,0,0);
	/* increase sigGenerator priority to allow sigGenerator to run */
	taskPrioritySet(ownId,HIGHPRIORITY); 
}